The present invention relates to an applicator for a product, such as a semi-fluid product, for example, wherein the applicator includes an applicator wall.
In general, a semi-fluid product as defined herein is to be understood as being a viscous product having a consistency such that it may flow under the effect of its own weight. By way of example, such a product may be in the form of a cream, a paste or a gel.
Optionally, the applicator is intended to apply topically a product with a cosmetic or dermopharmaceutical action, such as a deodorant, scented product, thinning product, depilatory cream, a face cream, and/or a gel for treating the scalp, for example.
The applicator, according to an optional aspect, may be of the type comprising a body having an end closed by a product-permeable applicator wall. The applicator may comprise a piston capable of sliding in a sealed manner against an interior wall of the body and of passing from a first position in which the piston may be at substantially a maximum distance from the applicator wall to a second position in which the piston may be at substantially a minimum distance from the applicator wall. The applicator may comprise a rod associated with a drive mechanism, for example, a mechanism with a screw thread in combination with a rotary knob, for driving the piston towards the second position and forcing the product through the applicator wall.
In another optional aspect, the present invention may relate to an applicator of the aforementioned type, which is filled from the bottom, that is to say from the opposite end of the body to the applicator portion of the applicator.
DE 2 027 483 describes an applicator having a container with an internal cross section in a circular shape. The applicator portion consists of an attached element having an orifice at its center. The applicator portion is in the form of a sponge having a hole at its center, or a wall made of polyethylene and having an exterior surface with spiral grooves for distributing product that comes out of a single central orifice. The disadvantages of a structure such as this are many. The circular shape of the body of the container, and therefore of the piston, mean that in order to prevent the latter from turning, it has to be mounted very tightly inside the body, particularly via an elastic steel filament, which forces the piston to press constantly against the internal walls of the container. Operation of such a circular applicator device may require a relatively large force to cause the piston to travel towards the applicator portion.
Added to this potential disadvantage is the additional assembly step dictated by the fact that the applicator portion is attached. Furthermore, the presence of a single central orifice means that the central orifice has to be produced with a relatively large cross section. As a result, unless the cap comprises an element that, in the closed position, becomes inserted inside the central orifice so as to seal it off, the risk of inadvertent dispensing of product when the device is in the storage position is relatively high. Furthermore, despite the presence of grooves on the applicator surface, product is not spread out over the applicator surface as uniformly as it might be. Additionally, the grooves are sources of soiling of the applicator surface.
U.S. Pat. No. 4,298,036 describes an applicator having a product that can be filled from the bottom via a hollow part of a shaft that drives a plunger. Air escapes through a hole provided in the plunger. An end of the housing in the filling position is delimited by an inner piece with a desired profile, and held in position, for example by means of a removable cap. After a certain period, the product sets to form a solid stick. Upon first use, the user removes the inner piece and applies the product, using the upper surface of the stick itself as the applicator surface.
Apart from the absence of an applicator wall capable of xe2x80x9cclosingxe2x80x9d the body at an application end, throughout the life of the applicator, the position of the vent orifice in the plunger makes the use of such an applicator inappropriate for a stick other than a solid one. This is because, in the case of a semi-liquid product, for example a creamy product, a certain amount of product would inevitably escape through the vent orifice under the pressure generated by the movement of the plunger. This leakage would contaminate at least the portion of the applicator situated beneath the plunger.
Elsewhere, there are devices in which the piston and the mechanism that drives the piston are mounted after filling from the bottom and thus do not provide a channel for filling the applicator while the piston is in place on the applicator. The problem with such a configuration lies in the difficulty to achieve this assembly after filling. That is to say with product present. In an assembly environment using industrial tooling, for example, there may exist substantial risks of some of the product escaping from the housing and soiling the mechanism.
Filling the housing of the applicator from the top may preclude producing the applicator portion in the form of an apertured wall obtained by molding with the body of the applicator. Furthermore, mounting an applicator portion, for example in the form of a grating or of a porous element, after the housing has been filled, may prove difficult in an industrial production environment.
Hence, one of the optional aspects of the invention may be to provide an applicator that may solve one or more of the problems discussed hereinabove with reference to certain conventional devices.
One aspect of the invention may be to produce such an applicator that may be simple and economical to produce. Another aspect of the invention may be to provide an applicator that may be relatively simple and economical to fill, for example, on an industrial production line. Yet another aspect of the invention may be to produce an applicator with a configuration that may be filled on an industrial production line, for example, while reducing the risks of product soiling the outside of the housing.
Other further aspects will become apparent from the detailed description that follows.
According to the invention, there is an applicator, for example for a cosmetic product, comprising a body having an interior and one end closed by an applicator wall. The applicator may further comprise a piston capable of sliding in a sealed manner along an interior of the body, and a rod associated with a drive mechanism for driving the piston towards the applicator wall to cause or force product to pass through the applicator wall.
The rod may have passing through it, over at least part of its length, a channel configured to open onto the outside of the body via a first opening and also opening into the body via at least one second opening. The at least one second opening may be arranged between the piston and the applicator wall when the piston is substantially a maximum distance away from the applicator wall. The rod may also have passing through it at least one vent orifice configured to allow air to escape, for example, while the body is being filled with product via the channel.
The body may be of non-circular interior cross section, and/or the applicator wall may be made of a single-piece unit with the body, for example by molding. The applicator wall may optionally have, passing through it, a number of orifices. The configuration of these orifices may allow product to be spread in such a way as to distribute the product over substantially the entire surface of the applicator wall.
A non-circular (for example rectangular, ovoid or elliptical) shape of the internal cross section of the body may allow the piston to be prevented from rotating within the body without special immobilizing means or without demanding a substantially high bearing force between the peripheral lip of the piston and the internal surface of the body. Operation may, therefore, be easier.
The applicator according to one aspect of the invention may be relatively simple to assemble because the body and the applicator wall may be produced as a single piece. This also may make it possible to get around the problems of sealing that could result from an arrangement in which the applicator wall were attached to the body as a separate piece.
Unlike a configuration with one single central orifice, a small cross section of many orifices in the configuration according to one aspect the invention may allow the use of the device for products, for example, of lower viscosity and may reduce the risk of inadvertent dispensing of product that may result from pressure accidentally exerted on one or more of the walls of the container when the container is in a storage position. As a result, it may not be necessary to provide elements to close off these orifices when the applicator is in a closed position. Furthermore, spreading of product over the surface of the applicator wall may be better than in conventional devices.
According to another aspect, the volume formed between the piston and the applicator wall could be filled with product through the channel in the rod. If done in this manner, a stopper may be fitted to close off the first opening. The stopper could, for example, be fitted on an industrial production line. This could allow the fitting of the stopper to be carried out automatically with a minimized risk of the applicator or its environment being soiled with product.
Because of a pressure gradient that may exist between the region of the applicator wall and the inside of the rod, at the location where the vent orifices may be formed, a risk of product escaping from the area defined between the piston and the applicator wall, such as towards the actuating mechanism, when the piston is driven towards the applicator wall, may be appreciably reduced. These risks may also be reduced by the fact that the cross section of the vent orifice may be negligible by comparison with the total cross section of the orifices in the applicator wall.
The at least one vent orifice may be arranged in such a way that during filling, it may lie above a maximum level of product. This may allow the vent to be effective throughout the filling period. As an option, the at least one vent orifice may arranged near the piston when the piston is substantially a maximum distance away from the applicator wall, but still engaged with the rod.
A maximum diameter of the vent orifice(s) may be chosen, for example, according to a viscosity of the product intended to be contained in the applicator. The maximum diameter may be chosen so that if there is no appreciable raised pressure inside the container, the product may not flow out through the orifices of the applicator wall under the effect of its own weight. Thus, the more viscous the product, the larger the cross section of the vent orifice may be. Typically, the vent orifice(s) may have a diameter of from about 0.3 mm to about 1 mm.
In addition, the applicator wall may have practically no orifice facing a free or second end of the rod so as to cause the portion of the applicator wall without orifices to be impermeable to product. This impermeable portion facing the rod could optionally have approximately the same cross-section as the rod. The presence of orifices directly in the axis of the rod, particularly when the product is introduced at a relatively high rate, could allow, during filling, product to pass between the applicator wall and the cap or between the applicator wall and a removable inner seal that may be present during filling. This may result in soiling of either of the internal surface of the stopper or of the applicator surface. Alternatively, the channel passing through the rod may not open axially.
The orifices passing through the applicator wall may be from 20 to 50 in number. The diameter of the holes may be on the order of about 1 to about 1.5 mm.
According to an exemplary embodiment, the rod may have a screw threading capable of engaging with a corresponding screw threading provided on the piston. These screw threadings could allow driving the piston towards the applicator wall in response to an actuating command exerted, for example, on a rotary knob. Alternatively, the drive mechanism may include a ratchet mechanism associated with a button that may be pushed in to cause the piston to advance within the body.
The at least one other opening may be arranged near a free end of the rod situated near the applicator wall. As an option, the at least one second opening may open laterally or radially from the rod. The rod may define one or more of these lateral openings for communication with the body. As an option, the rod may comprise at least two lateral or radial openings that may open away from one another on the rod.
To allow for an easier release of the rod if made by a molding process, the lateral openings may open onto an edge formed by the free end of the rod.
The free end of the rod may be in contact with an interior surface of the applicator wall. Thus, if the rod is hollow along substantially its entire length, and ends in an axial opening, the axial opening may be closed off in a substantially impervious manner by the interior surface of the applicator wall. The free end may, however, be at a non-zero distance from the interior surface of the applicator wall, which could allow for an increase of the filling rate.
The end of the body at the opposite end of the applicator wall may have an attached bottom. The attached bottom may have an opening communicating with the first opening of the channel. This bottom may allow the applicator to be produced in the form of a more or less closed volume.
The first opening of the channel may, after filling, be closed off by a stopper. The stopper could be fixed, for example, by snap-fastening, bonding, screwing, and/or welding. Within the meaning of the present invention, the term xe2x80x9cstopperxe2x80x9d includes any element capable of sealing the first opening. It may also be a bonded or heat-sealed inner seal.
Depending on the rheology of the product, and on the general configuration of the applicator, it may be desirable, after filling, to close off the vent orifice in such a way as to ensure that substantially no product may flow through the vent orifice, for example, under thrust of the piston. Additionally, a portion of the stopper closing off the first opening may be configured in such a way that, if mounted on the applicator, it may isolate the inside of the rod from the outside of the rod. A skirt that may be used to attach the stopper to the applicator may be extended so that it extends at least as far as the at least one vent orifice, so as to close it or them off.
Optionally, the applicator according to an aspect of the invention may comprise a cap mounted removably, for example by clipping, on the body so as to isolate the applicator wall in a substantially impervious manner from the outside.
As an option, a removable inner seal that is substantially impervious to product may be fixed, prior to first use, to the applicator wall, for example by bonding or heat sealing. An inner seal, aside from being able to protect the cap during filling, may constitute evidence of tampering. Alternatively, it may improve the impervious nature of the applicator, for example, while it is being transported or stored prior to its first use.
The applicator according to an aspect of the invention may be used for applying, for example, a cosmetic product, such as in the form of a cream, a gel, or a paste.